Allosteric regulation of small-molecule binding to aptamers

Modular aptameric sensors for oligonucleotides were constructed by combining molecular beacon stem-loops and malachite green aptamers. These sensors were designed so that oligonucleotides complementary to the stem-loop region accomplish the release of malachite green from its binding module. The oligonucleotides that bound to both loop and stem caused efficient release of the dye. While this sytem is not suitable for single-mismatch detection, it represents proof-of-concept for drug delivery components of autonomous therapeutic devices on a molecular scale.